t = int(input())
x = [int(input()) for _ in range(t)]
p = x[0]
if p != 1 and p != -1:
    print("F")
    exit()
for i in range(1, t):
    if abs(p - x[i]) != 1:
        print("F")
        break
    p = x[i]
else:
    print("T")